The protective role of vitamins C and E in steroid-induced femoral head osteonecrosis: An experimental study in rats.

OBJECTIVES: This study aimed to determine whether vitamin C (VC) and vitamin E (VE) can effectively protect the femoral head and reduce the risk of developing osteonecrosis in rats that have been treated with steroids. MATERIALS AND METHODS: The study was conducted on 30 young adult male Sprague-Dawley rats (mean weight: 356±18 g; range, 330 to 375 g), which were randomly assigned to one of five groups. The control group received saline solution, while the other groups were given lipopolysaccharide/methylprednisolone (LPS/MPS) to induce osteonecrosis. Three groups in which osteonecrosis was induced were also intraperitoneally administered either VC, VE, or both once a day for four weeks. Intracardiac blood samples were taken at the end of the fourth week for biochemical examination, and the rats were then sacrificed under general anesthesia. After sacrification, right femurs were removed for histopathological, immunohistochemical, and radiologic examinations. RESULTS: The results showed that the mean trabecular number increased significantly in the VC+VE group. There was a substantial decrease observed in the mean trabecular separation within the LPS/MPS group compared to the control group, although trabecular separation decreased in all three vitamin groups compared to the LPS/MPS group. The surface area/bone volume was significantly increased in the VC+VE group compared to the LPS/MPS group. Histological, immunohistochemical, and radiological examinations showed that the administration of VC and VE significantly reduced oxidative stress, inflammation, and microvascular dysfunction in rats with steroid-induced femoral head osteonecrosis. CONCLUSION: This study suggests that VC, VE, and particularly VC+VE have a protective effect on the femoral head in rats with steroid-induced femoral head osteonecrosis. These findings may lead to new treatment options for patients.

The effects of thymoquinone on steroid-induced femoral head osteonecrosis: An experimental study in rats.

OBJECTIVES: In this study, we aimed to evaluate the antioxidant, anti-apoptotic, osteoblastic and hypolipidemic effects of thymoquinone (TQ) treatment on the steroid-induced osteonecrosis of femoral head (ONFH) model in rats. MATERIALS AND METHODS: A total of 24 rats were randomly divided into four groups: the control group administered saline; the TQ group administered 10 mg/kg/day TQ orally; lipopolysaccharide/methylprednisolone (LPS/MPS) group administered 20 µg/kg intraperitoneally LPS and 40 mg/kg intramuscularly MPS to establish ONFH model; and the LPS/ MPS+TQ group administered both LPS/MPS and, then, TQ once daily for four weeks. All rats were sacrificed after intracardiac blood collection and their right femurs were removed. RESULTS: Micro-computed tomography showed a higher bone mineral density and lower porosity, Tr. Sp and Tr. Sep data were detected in the LPS/MPS+TQ group. In histopathology, osteonecrosis increased significantly in the LPS/MPS group and osteonecrosis decreased in the LPS/MPS+TQ group compared to the LPS/MPS group (p=0.0077). Histomorphometric examination revealed that the percentage of BV/TV in the LPS/MPS group was significantly lower compared to control and other groups (p<0.01 and p<0.05, respectively), while it reached normal rates in the LPS/MPS+TQ group. Immunohistochemically, antioxidant, anti-apoptotic, and angiogenesis indicators (8-hydroxy-20- deoxyguanosine [8-OHdG], malondialdehyde [MDA], B-cell lymphoma [Bcl-2], caspase-3, vascular endothelial growth factor [VEGF]) were significantly improved in tissue and serum with TQ. Furthermore, TQ significantly reduced low- and high-density lipoprotein cholesterol ratio and carboxy-terminal type 1 collagen crosslink (CTX) in serum. CONCLUSION: Vascular and hematopoietic cell damages that occur due to steroid-induced deoxyribonucleic acid (DNA) oxidative and lipid peroxidative damages in an ONFH model can be successfully ameliorated by TQ administration. This antioxidant and anti-apoptotic effects of TQ may be a promising treatment option for early stage of osteonecrosis.

Effects of social stress and fluoxetine treatment on fracture healing in a rat femur fracture model.

BACKGROUND: Mental stress and depressive disorders have negative effect on bone biology and increase fracture risk. Fluoxetine is a widely used selective serotonin reuptake inhibitor in the treatment of these disorders. We aimed to evaluate the effects of social stress and fluoxetine treatment on fracture healing. METHODS: This study was performed with 32 male Sprague-Dawley® rats. Rats were randomly divided into four groups with eight rats in each group. Social stress regimen was performed in groups 3 and 4 for 15 days. Placebo for groups 1 and 3 and fluoxetine for groups 2 and 4 was administrated. Rat femur open (osteotomy) fracture model was performed. Placebo and fluoxetine were continued to be given to the same groups for four weeks until sacrification of animals. Sacrificed right femurs of subjects were evaluated histologically and radiologically. The obtained data were statistically analyzed using the SPSS 23 (Statistical Package for the Social Sciences) program. RESULTS: Fracture healing score that evaluates the fracture healing quantitatively based on histological scale and bone mineral density of group 3 were significantly lower than other groups, and there was no significant difference between other groups. Inflammation score of group 2 was significantly lower than group 3. Group 1 had higher new callus formation/original cortex volume than group 2 and group 3. In immunohistochemical evaluation, the H-score of BMP-7/osteoblast in group 3 was lower than in group 1. The H-score of CD34 in group 3 was lower than in group 1. DISCUSSION: The positive and negative effects of fluoxetine, which is used in the treatment of depressive disorders, on wound, tendon, or bone healing have been shown in the literature. In this study, we showed the negative effects of depression on the early stages of fracture healing. Although fluoxetine had no detrimental effect on fracture healing in non-depressive rats, impaired fracture healing was reversed and better radiological and histological findings were obtained in depressive rats treated with fluoxetine. Our findings indicate that fluoxetine, which minimizes the negative effects of social stress on bone healing, can be used safely in the treatment of depressive disorders in patients with fractures.

Effects of different vardenafil doses on bone healing in a rat fracture model.

OBJECTIVES: We aimed to investigate the radiological, biomechanical, histopathological, histomorphometric, and immunohistochemical effects of different doses of vardenafil on fracture healing. MATERIALS AND METHODS: Fifty-one rats were divided into three groups. Group V5 was given 5 mg/kg/day of vardenafil; Group V10 was given 10 mg/kg/day of vardenafil; and the control group was given the same volume of saline. Six rats from each group were sacrificed on Day 14 (early period) and the remaining rats were sacrificed on Day 42 (late period). Callus/femoral volume and bone mineral density were measured using micro-computed tomography. Five femurs from each group in the late period were examined by biomechanical tests. In addition to the histopathological and histomorphometric evaluations, immunohistochemical analyses were performed to examine the levels of inducible nitric oxide synthase (iNOS), transforming growth factor-3 (TGF-ß3), and nuclear factor kappa B (NF-κB) proteins. RESULTS: Both doses of vardenafil increased primary bone volume and maximal bone fracture strength in late period, compared to the control group (p<0.05). Histological healing scores of vardenafil groups were significantly higher in early period (p<0.001). While cartilaginous callus/total callus ratio in early period was higher, callus diameter/femoral diameter ratio in late period was lower in vardenafil groups (p<0.01). The NF-κB immunopositivity in V10 group decreased in early period, compared to control group (p<0.001). The TGF-ß3 and iNOS immunopositivity increased in both V5 and V10 groups, compared to the control group in early period, but returned to normal in late period. CONCLUSION: During the first period of fracture healing process in which vasodilation is mostly required with increasing inflammation, vardenafil has ameliorating effects on the bone union and supports fracture healing.

Factors affecting re-displacement in pediatric forearm fractures and the role of cast indices.

OBJECTIVES: This study aims to investigate the factors affecting the loss of reduction in pediatric diaphyseal forearm fractures and to compare the three-point index (TPI) with the cast index, padding index, Canterbury index, and gap index. PATIENTS AND METHODS: This retrospective study, which was conducted between January 2016 and December 2016, included 159 patients (134 males, 25 females; mean age 8.1±2.8 years; range, 3 to 13 years) with diaphyseal forearm fracture. Patients' age, gender, and the level, displacement, and location of the fractures were recorded. The presence of anatomic reduction, a straight ulnar border, and the cast type (banana or box type) were checked after the reduction. The TPI, cast index, padding index, Canterbury index, and gap index were measured. RESULTS: Fifty-two patients (32.7%) experienced loss of reduction during the follow-up. Displaced fractures of both the radius and the ulna, cast type-banana, anatomical reduction, straight ulnar border, TPI, cast index, padding index, and Canterbury index were found to be associated with re-displacement. CONCLUSION: Although cast indices can be used as a beneficial clinical tool in predicting the loss of reduction in the treatment of pediatric forearm fractures, they may not be sufficient when used alone. Obtaining a more accurate result may be possible by assessing several parameters such as the presence of an anatomic reduction, box-type casting, and TPI together.

Histopathological, immunohistochemical, and biomechanical effects of splenectomy on Achilles tendon healing in rats.

PURPOSE: This study aimed to assess Achilles tendon repair in rats following splenectomy to simulate patients with musculoskeletal system injury who had splenectomy after spleen injury, a situation often seen in orthopedics and traumatology practice. MATERIALS AND METHODS: The study included 32 male Sprague-Dawley rats (10 months old; average weight, 394.5 ± 28.3 g). The rats were fed with standard rodent food ad libitum at 22°C in a dark environment for 12 h. They were divided into two groups, namely the splenectomy (total splenectomy and Achilles tendon repair) and control groups (only Achilles tendon repair; n = 16). Four weeks after the surgery, the rats were euthanized, and their Achilles tendons were examined histopathologically, immunohistochemically, and biomechanically. RESULTS: In the splenectomy group, proinflammatory cytokines, such as interleukin-1ß, tumor necrosis factor-α, and interferon-γ, showed significantly lower values than those in the control group (p ˂0.01); moreover, the levels of anti-inflammatory cytokines like vascular endothelial growth factor, transforming growth factor-ß1, interleukin-2, interleukin-10, and hepatocyte growth factor were significantly higher than in the control group (p ˂ 0.001). The average ultimate tensile strengths were 2.58 ± 0.5 in the splenectomy and 2.78 ± 0.3 in the control group (p = 0.043). The average εUTS values were 0.33 ± 0.5 in the splenectomy and 0.44 ± 0.1 in the control group (p = 0.021). CONCLUSION: Splenectomy may positively influence Achilles tendon healing through modification of the proinflammatory/anti-inflammatory ratio in favor of anti-inflammatory cytokines by causing a decrease in spleen-originated inflammatory cells.

Biomechanical, histological, and radiological effects of different phosphodiesterase inhibitors on femoral fracture healing in rats.

PURPOSE: To investigate the biomechanical, histological, and radiological effects of sildenafil and pentoxifylline on femoral fracture healing in rats. METHODS: Forty-eight Sprague-Dawley rats were divided into three groups equally according to the pharmacological agents to be investigated. Femoral shaft fractures were formed in the left side. Group 1 (control group), group 2, and group 3 were administered with saline, sildenafil, and pentoxifylline during the fracture healing process, respectively. Eight rats from each group were euthanized on days 15 and 30. X-ray images of the rats were taken after euthanasia for radiographical examination. Femur samples were subjected to histopathological and biomechanical (three-point bending) examinations. RESULTS: Radiologically, no difference between the Goldberg scores of the groups was found for day 15 ( p > 0.05), while higher Goldberg scores were obtained from group 2 than that of group 1 ( p > 0.05) and group 3 ( p < 0.05) for day 30. In the biomechanical analysis, higher mean breaking forces were found both for day 15 and day 30 from group 2 than those obtained from group 1 (for day 15 p > 0.05 and day 30 p > 0.05) and group 3 (for day 15 p < 0.05 and day 30 p < 0.01). Higher mean absorbed energy values were obtained from group 2 than those obtained from group 1 (for day 15 p > 0.05 and day 30 p < 0.05) and group 3 (for day 15 p < 0.01 and day 30 p < 0.01). A significant difference was not found between the histological scores of all groups ( p > 0.05) for day 15, while the histological score of group 1 on day 30 was found to be significantly lower than that of sildenafil and pentoxifylline groups ( p < 0.05). CONCLUSION: Sildenafil had a positive effect on fracture healing, while pentoxifylline did not provide consistent positive effect.

Comparison of intramedullary nailing and minimal invasive plate osteosynthesis in the treatment of simple intra-articular fractures of the distal tibia (AO-OTA type 43 C1-C2).

OBJECTIVE: The aim of this study was to compare midterm functional and radiographic results of minimal invasive plate osteosynthesis (MIPO) with intramedullary nailing (IMN) of simple intra-articular distal tibial fractures (AO-OTA type 43 C1-C2). METHODS: Seventy-three simple intra-articular distal tibial fracture patients were evaluated retrospectively. All were treated between 2009 and 2014. The average age of the patients was 40.3 years. Thirty-seven patients were treated with IMN and 36 patients were treated with MIPO. Fibular plate osteosynthesis was applied in 5 cases (13.5%) in the IMN group and in 23 patients (63.9%) in the MIPO group. RESULTS: Functional results and complications of IMN and MIPO methods were assessed in 73 patients. The average union time was 16.4 ± 2.7 weeks in the IMN group and 15.2 ± 1.8 weeks in the MIPO group (p = 0.079). The average Olerud-Molander Ankle Score was 87.8 ± 8.1 in the IMN group and 81.5 ± 11.8 in the MIPO group (p = 0.013). Four patients in the IMN group experienced valgus malunion, while it was not observed in any patients in the MIPO group (p = 0.042). Recurvatum malunion was detected in 10 patients in the MIPO group and not seen in the IMN group (p = 0.001). Ankle dorsiflexion angle was 25.8 ± 4.5° in the IMN group and 33.3 ± 8.9° in the MIPO group (p = 0.000). CONCLUSION: Simple intra-articular distal tibial fractures are successfully treated with IMN and MIPO. Prevalence of valgus malunion was higher in the IMN group and recurvatum was more prevalent in the MIPO group. MIPO is the first preference according to the literature; however, successful results have been obtained with IMN in this fracture pattern. LEVEL OF EVIDENCE: Level III, Therapeutic Study.

Effect of platelet-rich plasma for treatment of Achilles tendons in free-moving rats after surgical incision and treatment.

OBJECTIVE: The purpose of this study is to investigate, both histopathologically and biomechanically, the effect of platelet-rich plasma (PRP) on surgically repaired Achilles tendon rupture recovery in rats. METHODS: The study included 25 17-month-old male Sprague-Dawley rats with an average weight of 500-550 g. Five rats were used as donors, while 20 rats were separated as PRP group (n=10) and control group (n=10). The Achilles tendons of the rats were cut transversely, and PRP was administered to the PRP group, while the control group received serum physiologically to create the same surgical effect. In previous studies, it was shown that this serum does not affect tendon recovery. Fifteen and 30 days post-treatment, the rats were sacrificed, and their Achilles tendons were extracted and examined histopathologically and biomechanically. RESULTS: Based on the obtained findings, it was observed that the histopathologic Movin and Bonar scores of PRP group on the 15th and 30th day post-treatment were significantly lower than those of the control group (p=0.019, p=0.017, respectively), while no significant difference was found in maximum force (Fmax) values in biomechanical measures on the 15th and 30th day post-treatment. CONCLUSION: It is thought that PRP use in Achilles tendon ruptures positively affects histopathological recovery in the early period, but that it does not produce the same biomechanical effect. We believe that PRP use for qualified tendon recovery is histopathologically beneficial.

Risk factors in redisplacement of distal radial fractures in children.

BACKGROUND: The causes of redisplacement following closed treatment of distal metaphyseal radial fractures in children are still controversial. Various risk factors and radiographic indices have been suggested to predict redisplacement. The aims of this study were to prospectively identify the causes of redisplacement and to test the accuracy of previously described radiographic indices and our new method, the "three-point index." METHODS: This prospective study included seventy-five displaced or severely angulated distal radial fractures in seventy-four children under the age of fifteen years. Age, gender, initial complete displacement of the radius, an associated ulnar fracture, the accuracy of the reduction, the maximum degree of obliquity of the fracture line in the sagittal or coronal plane, and the distance to the physis were examined as possible risk factors. Logistic regression analysis was utilized to search for risk factors. We also calculated the cast index, padding index, Canterbury index, gap index, and three-point index on the radiographs of each reduction. The sensitivity, specificity, negative predictive value, and positive predictive value were calculated for each test. RESULTS: Initial complete displacement and the degree of obliquity of the fracture were the most important risk factors for redisplacement. Fractures that were completely displaced initially were 11.7 times more likely to redisplace than were angulated but incompletely displaced fractures. A 20 degree oblique fracture was 4.9 times more likely to redisplace and a 30 degree oblique fracture was 10.9 times more likely to redisplace than was a 0 degree true transverse fracture. The three-point index was superior to the other radiographic indices for predicting redisplacement, with a sensitivity of 94.7%, a specificity of 95.2%, a negative predictive value of 98.4%, and a positive predictive value of 85.7%. The gap index was the next-best measure, but it had a sensitivity of 63.2%, a specificity of 76.2%, a negative predictive value of 87.3%, and a positive predictive value of 44.4%. CONCLUSIONS: Initial complete displacement and the degree of obliquity of the fracture line are the dominant factors affecting redisplacement. Our new radiographic index, the three-point index, should be used to predict redisplacement and assess the quality of the cast treatment of these fractures.